The invention relates to a sealing connecting element, a sealing end piece and a seal.
Seals are used in a number of areas of daily life, in order to seal off specific spaces from each other or from the environment in a liquid- and/or gas-tight manner. A particularly important area of application for seals is that of doors and flaps, at which in part large sealing gaps regularly occur owing to inaccuracies in the assembly process.
One particular area of application for seals is motor vehicle construction, in which there are usually extremely high demands placed upon the sealing behavior of a seal and its load capability with respect to environmental influences, such as temperature fluctuations, UV-radiation, the influence of solvents and other environmental factors. In order to be able to guarantee a long serviceable life under possibly extreme environmental conditions, it is known in practice to use elastomer seals. The materials most frequently used for these types of elastomer seals are EPDM (ethylene-propylene-diene-copolymers), NBR (natural butadiene rubber), NR/SBR-blends and CR-materials (controlled rheology polypropylene materials).
It is known in practice to process the said materials to form strip profiles which are then tailored to suit the specific requirements by being cut and adhered to form three-dimensional structures. It is also known in practice to connect the EPDM-sealing profiles at their corners by means of a TPE-V-injection molding technique (book: Thermoplastische Elastomerexe2x80x94Herausforderung an die Elastomerverarbeiter/VDI-Gesellschaft Kunsstofftechnik, [thermoplastic elastomersxe2x80x94challenge to the elastomer manufacturers/VDI-Gesellschaft synthetic material technology], VDI-Verlag GmbH 1997, page 145). In the said three-dimensional structures, the seals are then given to the customers who install them into vehicles or other structures.
In order to be competitive in the market, it is necessary to provide in a rapid manner large quantities of seals which can be assembled in a convenient manner. Owing to its flexibility during processing, the sealing strip material places high demands upon the persons employed in the manufacturing process.
It is known per se from JP 01 186447 A to insert the end faces of two sealing profile strips into a hard polyamide coupling piece and to adhere them together.
It is known per se from JP 58 224810 A to seal window sealing profiles, which abut each other in a flush manner, with respect to each other by virtue of a locally integrally-formed sealing lip.
DE 36 29 343 A1 illustrates as being known per se a corner connector with tapered mandrels and in each case a profile strip is attached and adhered thereto with a hollow space.
It is known per se from U.S. Pat. No. 4,712,826 A to attach a window to the bodywork of a motor vehicle. For this purpose, the window, sealing profiles and a corner piece are placed in position. Then, the intermediate spaces are filled with a sealing adhesive.
According to EP 0 395 444 A1, an end cap is pushed in a manner known per se on to an open end face of a clamping profile, the clamping profile having been placed on to a bodywork flange beforehand.
It is known per se from EP 0 378 419 A1, FIGS. 1 and 5, to attach a holding device for a rear-view mirror to a window channel structure. The holding device comprises an end piece which is partially coated with polymer. Connection spigots of adjoining frame profiles have a rectangular cross-section and are inserted into an open receiving channel of the end piece.
U.S. Pat. No. 5,007,761 illustrates as known per se the releasable connection of a window compartment seal to a door seal for a coupxc3xa9. A transition piece is vulcanized to the window compartment seal. The transition piece comprises a recess, into which it is possible to insert an upper end of the door seal from below. In this inserted state, the connection is secured in an axial manner by virtue of a claw of the transition piece, which claw engages into a complementary recess of the door seal.
In accordance with DE 42 43 043 A1, it is known per se to attach together in a flush manner two ends of a clamping profile which comprises a textile coating. The clamping profile comprises a sealing tube, into the hollow space of which a complementary, rubber-elastic spigot is introduced in each case with a part of its length as a coupling element.
It is the object of the invention to simplify the production of seals.
The object is achieved in accordance with the invention by a sealing connecting element for connecting in a sealing manner at least one first and one second sealing profile strip whose ends are not aligned with each other, and which sealing connecting element is formed separately from the sealing profile strips as a molded part with a profile guide region from a thermoplastic elastomer. The profile guide region of the connecting element moves into position against an outer wall of an inserted sealing profile strip. The invention further provides a sealing end piece for sealing profile strips which are formed separately from the sealing profile strips as a molded part with a profile guide region from a thermoplastic elastomer, wherein the profile guide region moves into position against an outer wall of an inserted sealing profile strip. The invention further provides a seal having at least one sealing profile strip and one sealing connecting element according to the above.
It is provided in accordance with the invention, to produce sealing connecting elements and/or sealing end pieces as separate molded parts from a thermoplastic elastomer and only to connect these molded parts to sealing profile strips to form a complete seal shortly prior to the installation of a seal. The fact that the sealing connecting elements and/or sealing end pieces on the one hand or sealing profile strips on the other hand are produced separately and are transported separately serves on the one hand to simplify the production of the individual parts and on the other hand serves to minimize the transportation cost. Whereas it is necessary in the prior art to position sealing profile strips manually in a corresponding mold for the connection by means of an adhesive or an injection-molded TPE-corner piece, it is possible for the production of the sealing connecting elements and sealing end pieces according to the invention to be fully automated.
After transporting the individual sealing parts which requires less space than complete seals, the said sealing parts can then be joined together in the form of a kit to form complete seals, in that sealing profile strips are moved into position against the profile guide regions of the sealing connecting elements or sealing end pieces, wherein it is possible to join said sealing parts together in a particularly convenient manner if longer sealing profile strips are already attached and thus fixed to a rigid structure.
The thermoplastic elastomer sealing connecting elements and sealing end pieces in accordance with the invention provide a kit component which renders it possible when mounting a seal on a structure, which is not produced to precise dimensions, to react rapidly and readily by virtue of the fact that instead of a sealing profile strip of a predetermined length, a different sealing profile strip is used which has an individually tailored length. This minimizes assembly costs and rejects.
The kit concept which forms the basis of the seals in accordance with the invention and the sealing connecting elements and/or sealing end pieces used in said seals is particularly advantageous if large-capacity seals or small production-lots of seals are to be produced, since the ease of handling and the possibility of using standard components are particularly beneficial aspects.
Preferably, the profile guide region is formed having a thin wall, so that the arrangement between the outer contour of the sealing profile strip and the outer contour of the sealing connecting element is only slightly offset. This offset arrangement and an associated failure in the sealing arrangement can be minimized further if the profile guide region runs out to zero, i.e. the region tapers to a point.
In the case of motor vehicle bodywork seals for the purpose of sealing the engine compartment, it is often desired to seal an installation part separately after providing a peripheral seal. At such points, three sealing profile strips meet each other and must be connected together. In order in this case to reduce the risk of failures in the sealing arrangement and to reduce assembly costs, it is advantageous to design a holding portion of the sealing connecting element in such a manner that it can be attached to a continues sealing profile strip.
A particularly convenient assembly process is achieved if the sealing connecting element in accordance with the invention comprises a holding portion for clamping the connecting element to a sealing profile strip which is to be connected. In this case, it is possible to dispense with the process of adhering or welding the sealing connecting element to the respective sealing profile strip.
If an adhesion or welding process is performed to guarantee a permanent connection of the individual sealing components, it is advantageous to provide the sealing connecting elements with a stop which is formed as a counter bearing for sealing profile strips which are to be connected to the connecting element in an inserting manner. This type of design ensures straightforward assembly, particularly if the sealing connecting elements have a small over-dimension with respect to the respective sealing profile strips.
The production of complicated seals in small production-lots is simplified if different sealing connecting elements, which are preferably mirror-symmetrical with respect to a miter plane, are available with respect to a sealing profile strip type. In a similar manner to sanitary installation waste water pipe bends, these sealing connecting elements can then be joined together in an extremely convenient manner with sealing profile strips to form a desired three-dimensional structure.